In 2014, the Council of the European Union adopted the Directive 2014/87/EURATOM amending the 2009 Nuclear Safety Directive to incorporate lessons learned following the accident at the Fukushima Daiichi nuclear power plant in 2011. Recognising the importance of peer review in delivering continuous improvement to nuclear safety, the revised Nuclear Safety Directive introduces a European system of topical peer reviews which will begin in 2017 and every six years thereafter. The introduction of topical peer reviews was largely inspired by the peer review process used during the nuclear stress tests undertaken after the Fukushima accident, whilst here the assessments will each time focus on different specific technical safety aspects.
The 30th meeting of the European Nuclear Safety Regulators Group (ENSREG) in July 2015 identified "ageing management of nuclear power plants" as the topic for the first Topical Peer Review. This choice was made on the basis of a technical assessment performed by the Western European Nuclear Regulators Association (WENRA) in recognition of the age profile of the European nuclear reactor fleet and considering their potential long term operation.